[macOS/iOS export] Add option to set custom Info.plist data.

[bruvzg]

Fixes godotengine/godot-proposals#8848

[akien-mga]

It should probably mention what format is expected (maybe simply linking to the relevant Apple docs).

[bruvzg]

Added link to the Apple docs, and example.

[akien-mga]

How does it behave on export if the user puts invalid data / syntax errors? Do we export gracefully and then the .app would fail running? Is the error then clear enough?

Edit: If we want to do some validation on our side, we could likely check that XMLParser is happy with the syntax at least. Probably not worth implementing support for validating everything Apple would do itself though.

[bruvzg]

How does it behave on export if the user puts invalid data / syntax errors? Do we export gracefully and then the .app would fail running?

If it's completely invalid data, the app will run, but won't show info or have an icon. If it's valid fomatting but unknown keys/values, it will be ignored.

[bruvzg]

we could likely check that XMLParser is happy with the syntax at least.

It won't be enough, valid XML data is not necessarily valid part of <dict> element. Proper validation should check if it's matching http://www.apple.com/DTDs/PropertyList-1.0.dtd schema, but I do not think we have any code for this, and it probably is not worth adding for such minor feature.

[lostminds]

It won't be enough

You're right that it won't be enough to ensure it's a valid addition. But hopefully checking that it's valid xml should at least ensure the additions are correctly closed tags so the addition doesn't risk messing up the parsing of the entire Info.plist. If we can be reasonably sure about that it's a lesser problem if the content in the addition is just ignored if it's formatted incorrectly.

[akien-mga]

Yeah if it doesn't add significant complexity to the code, I think just validating that the syntax is valid XML would be enough.

[bruvzg]

We actually have a dedicated PList parser for ad-hoc code signing (which can give more verbose error output than XMLParser), so I guess it probably better to use it.

[bruvzg]

Added validation using PList parser from ad-hoc code signer, most likely it won't catch every error, since it's not designed to for validation, but should reject completely invalid data.

[akien-mga]

Thanks!